I noticed in a market I am in that there are several properties that are listed in the MLS that are below the comp values.

He purchased apartments for 60k which are now valued at 300k but it doesn't seem like they'll go up any higher.

My primary residence's current market value is $250k. 

This is a great place to start, but before you take on a BRRRs, you should look into projects that need some TLC which are turnkey under market value.  

I know the La Veleta area is desirable but I'm just wondering what's the smart/best value there.3. 

They will keep on going up as the assessed value of the house increases. 2.

Yes, as Eric says, the homes have to have all of the bells and whistles and even then you sometimes get screwed and don't get the rent value's you are seeking.

I also think it is really important to have a value proposition.

I'd decided in advance my maximum bid (figuring the taxes owed, the value of the lot and the cost of scraping the existing house if it came to that). 

Here's a snippet from our starter course on becoming a Local Real Estate Developer and it will help you understand where the value comes into a development project to see how to weight the equity and deal terms based on the experience of the partners in the deal.